Photocatalytic coated granules and method of making same

Abstract

These embodiments relate to a method of attaching photocatalytic materials to inorganic surfaces. A method is described wherein metal hydroxide is converted to metal oxide, creating metal oxide linkages to attach photocatalysts to an inorganic surface. The photocatalyst attached inorganic material is useful in products that can partially or fully oxidize certain volatile organic compounds from a gas or liquid stream.

The invention claimed is: 
     
       1. A photocatalytic composite comprising:
 pumice comprising 5-50 wt % Al 2 O 3  and 95-50 wt % SiO 2 , and 
 a photocatalytic compound comprising WO 3  and CeO 2 , 
 wherein at least two of Al 2 O 3 , SiO 2 , WO 3  and CeO 2  are chemically bonded together. 
 
     
     
       2. The photocatalytic composite according to  claim 1 , wherein the chemical bonding comprises an —O— linkage. 
     
     
       3. The photocatalytic composite according to  claim 1 , wherein said pumice further comprises 0-10 wt % of at least one of ferric oxide (Fe 2 O 3 ), calcium oxide (CaO), magnesium oxide (MgO), sulfur trioxide (SO 3 ), potassium oxide (K 2 O), sodium oxide (Na 2 O), or combinations thereof. 
     
     
       4. The photocatalytic composite according to  claim 1 , wherein said pumice comprises a porous granule. 
     
     
       5. The photocatalytic composite according to  claim 1 , wherein said pumice comprises powdered pumice.